The invention is based on a direction-finding method for determining an incident direction of a high-frequency electromagnetic signal with respect to a predeterminable primary direction of an antenna arrangement including at least two receiving antennas spaced apart a known distance for receiving the incident signal, wherein a phase difference is determined between the output signals of the receiving antennas and the incident direction of the signal is determined from the phase difference.
A method of this type is known per se, particularly in so-called interferometer direction finders. These are based on the use of at least two (receiving) antennas specified for a predeterminable frequency range, such as the high-frequency (HF) range. The antennas possess a predeterminable directional pattern, for example a so-called forward characteristic. That is, each antenna has a maximum receiving range of 180.degree. in, for example, the azimuth plane (parallel to the earth's surface). It is useful to orient the primary receiving directions of all antennas essentially parallel to one another, resulting in a common primary receiving direction. If a mono-frequency HF signal, for example, is incident at such an antenna arrangement from a direction other than the primary receiving direction, differences in transit times occur at the individual antennas, from which associated phase differences can be determined. The searched receiving direction (incident direction) of the HF signal (HF wave) can basically be determined from this phase difference between the received signals of two antennas.